Originally Posted by hardcore_gamer
The link you posted supports sergionography's post. From page 7...
Kind of depends how much you look into it:
GTX 680: Max OC 22%... Scaling: BF3 14.9%, Batman:AC 14.1%, Deus Ex 16.6%, Skyrim 5%...average 12.7% ( 0.58% gain per 1% OC)
HD 7970: Max OC 36%...Scaling: BF3 13.7%, Batman:AC 30.4%, Deus Ex 28.6%, Skyrim 20.9%...average 23.4% ( 0.65% gain per 1% OC)
Slight win for the HD 7970 there...
Second half of the equation...
GTX 680 power usage : Average 358w (OC by 22%), 339.5w (stock) = 0.84w increase per 1% OC
HD 7970 power usage: Average 540w (OC by 38%), 464w (stock) = 2w increase per 1% OC
(since [H] neglected to include the 7970's OC'ed power consumption in comparison to the 680
If you're talking performance only, then yes, the HD 7970 will certainly come out ahead since it's base core clock is effectively underclocked- basically the same scenario as measuring OC percentage for the GTX 560 Ti (and GTX 460 before it).
Since OC'ing tends to be limited by voltage and thus heat more often than not, I'd tend to take that into consideration. It's also not beyond the realms of possibility that GTX 600 BIOS will in future allow for a greater flexibility in OC potential- there's obviously some untapped potential
...which I'm guessing would even things up- the rationale being that with cards closer in OC percentage, the disparity in results would likely contract judging by reviews based on like-for-like OC ( i.e this TT review. Both cards OC'ed by ~22-23%
. The GTX 680 scales better in 6 of 8 games (admittedly a fair number are Nvidia-centric but that shouldn't work against the 7970 in scaling)